Sound propagation in urban areas

Abstract

An investigation of the propagation of sound from identifiable sources in urban areas has recently been concluded. As a result of this study, sound-level estimation procedures have been developed for typical configurations including: propagation through intersections, both single and multiple; propagation around corners, also both single and multiple; and propagation into side streets. These procedures apply to near-ground-level noise sources which are identifiable above background level and can be approximated by either a point or line source. Methods were developed for assessing the modification of the basic estimation procedures due to diffraction, ground interference effects, and sound-level nonuniformity across street sections near intersections. Additional modification of the basic estimation procedures accounting for building surface irregularities has been determined and can be used in sound-level prediction. Levels predicted by the estimation procedures have been compared with both field and model data. [Work supported by U. S. Department of Transportation and National Science Foundation.]